In recent years, integration of semiconductor substrates to form a semiconductor device using a through-silicon (or through-substrate) via (TSV) has attracted attention from the viewpoint of higher performance of the resulting semiconductor device.
In the integration technology using a TSV, stability of a through electrode formed in the TSV (also referred to as a TSV electrode) is very important. However, since a TSV has a high aspect ratio, it is difficult to embed a metal or the like into the hole in the substrate in which the TSV is to be formed.